Genome Property Definition Page

Namepolyphosphate kinase/exopolyphosphatase system
DescriptionThis property describes systems for polyphosphate metabolism, featuring a polyphosphate kinase (PPK1) and an exopolyphosphatase that often are encoded by adjacent genes. Polyphosphate can provide functions of phosphate and energy storage and may form granules. Genes from this system are often found next to genes of the inorganic phosphate transport system ( GenProp0190). Performing the comparative genomics for this system is tricky in part because of numbers of numerous apparent bifunctional proteins, exopolyphosphatase/guanosine pentaphosphate phosphohydrolase. Proteins of the polyphosphate kinase 2 (PPK2) family are largely restricted to species with PPK1 and help produce GTP from GDP and polyphosphate.
Parent PropertyGenProp0157: storage polymer systems
Literature References
[ 1 ] Brown MR, Kornberg A   Inorganic polyphosphate in the origin and survival of species.   Proc Natl Acad Sci U S A. 2004 Nov 16;101(46):16085-7.  PMID 15520374

Step NameStep NumRequiredEvidence (Method)Evidence Go Terms
polyphosphate kinase 1PP_ppk1YESPF02503 (HMM): polyphosphate kinase central domain
TIGR03705 (HMM): polyphosphate kinase 1
exopolyphosphatasePP_ppxYESTIGR03706 (HMM): exopolyphosphatase
PF02541 (HMM-CLUST): Ppx/GppA phosphatase family
polyphosphate kinase 2, PA0141 familyPP_useANOTIGR03707 (HMM): polyphosphate kinase 2
polyphosphate:AMP phosphotransferasePP_useBNOTIGR03708 (HMM): polyphosphate:AMP phosphotransferase
putative polyphosphate kinasePP_useCNOTIGR03709 (HMM): polyphosphate:nucleotide phosphotransferase, PPK2 family
polyphosphate kinase 2PP_useXNOPF03976 (HMM): polyphosphate kinase 2 (PPK0

Parent Properties
GenProp0157storage polymer systems

Sibling Properties
GenProp0055polyhydroxyalkanoic acids
GenProp0156cyanophycin-like storage polymers
GenProp0168glycogen system